Since pushing their first shovel into the ground 20 years ago, Jamestown archaeologists have rewritten the history of America's first permanent English settlement numerous times, beginning with the 1996 discovery of the landmark fort that most people believed had been lost.

Now they're probing the earth outside the perimeter of that iconic triangular citadel, searching for evidence of an early foothold that may have been much larger and more complex than many historians have thought.

Prompted by the previous discovery of two extensions to the palisade walls and the deliberate removal of an earlier wall — plus numerous questions raised by the settlers' own records — Jamestown Rediscovery director William M. Kelso and his team are looking intently for any telltale stains that may have been left by outlying palisades and the dug-out bases of temporary soldiers' tents as well as structures, wells and cultivated fields.

They're also trying to puzzle out the deceptive differences between today's landscape — which is marked by long rolling lawns and thick forest — and an early 1600s vista that may have incorporated as many as 30 to 40 acres of corn as well as large swaths of land cleared to maximize the effectiveness and range of the settlers' guns.

"We're getting a pretty good idea that this triangular fort — which is only about an acre — was the heart of a much bigger place. It was the stronghold — the keep of the castle," Kelso says.

"And what we're looking for is evidence of an early settlement that may have been acres and acres in size. We just have to follow the dots and see where they lead."

Among the most promising targets of the current excavation — which has been enlarged through the manpower boost provided by the project's summer field school — is a new square opened up just a few paces from where archaeologists found the remains of a corn field outside the original triangle this past summer.

The 2013 discovery of furrows as much as 50 feet long occupying at least half an acre all told made headlines by confounding oft-repeated claims about the colonists' lazy work habits.

It also piqued the archaeologists' interest in the new credibility of Capt. John Smith's previously unconfirmed reports that acres and acres of land had been cleared and planted after the settlers' 1607 arrival.

Whether or not the probe being conducted under the gaze of Jamestown's famous bronze statue of Pocahontas will turn up any new evidence, however, may take weeks to determine.

"It's difficult digging at this point," Kelso said.

"We have a gravel path to get through — and there's a lot of later landscaping that has to be sorted out — some of it dating to the early 1890s."

Two other sites outside the original triangle have been opened up, too, including a trench inside the Civil War earthwork erected at Jamestown in the early 1860s and a riverfront location originally excavated by the Jamestown team more than 15 years ago.

But so far the exposed layers of soil have not given up any secrets.

"There just isn't much left here because so much of it was scraped away during the Civil War," Kelso said. "But we want to make sure that nothing is overlooked."

Just how far the early settlement extended beyond the riverfront bastion is still a matter of debate and speculation, but there are plenty of tantalizing clues.

Numerous references from the period describe a blockhouse that stood about 600 yards to the north of the fort on a narrow strip of mud and sand connecting the colony to the mainland, archaeologist Danny Schmidt said.

Then there's the still unexplained section of palisade wall discovered about 200 yards to the north of the fort during the 2000-01 excavation of a relatively distant yet crowded burial ground believed to be associated with the Starving Time of 1609-10.

Combined with Smith's references to the corn fields — plus the harsh lessons the fort's early defenders learned from hostile Indians hiding in the surrounding tall grass — such features suggest that the first colonists may have significantly reshaped the original landscape outside the fort.

As early as 1608, the stronghold was reportedly running run short of room, making it likely though not certain that some sort of provisions for their shelter had to be erected outside the palisade walls.

"I think it's possible that the entire western tip of the island was pretty clear — that there was a clear line of sight all the way from the fort to the blockhouse — and that there was a lot going on in the space outside the fort," Schmidt said.

"An encampment doesn't necessarily leave you with a lot of evidence that can be found — but we've really just started looking"

Erickson can be reached at 757-247-4783. Find more Hampton Roads history stories at dailypress.com/history and Facebook.com/hrhistory.

Jamestown Rediscovery dig

Where: Historic Jamestowne, on Jamestown Island, west end of the Colonial Parkway, James City County

When: Daily until about 4 p.m., weather permitting.

Cost: Included in park admission of $14 adults, children 15 and under free

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